Support template unit files in podman generate systemd

Signed-off-by: Boaz Shuster <boaz.shuster.github@gmail.com>

3 files changed, 36 insertions, 4 deletions

diff --git a/pkg/systemd/generate/common.go b/pkg/systemd/generate/common.go
index 3515bb3b7..24c85a27e 100644
--- a/pkg/systemd/generate/common.go
+++ b/pkg/systemd/generate/common.go
@@ -23,7 +23,7 @@ func validateRestartPolicy(restart string) error {
 	return errors.Errorf("%s is not a valid restart policy", restart)
 }
 
-const headerTemplate = `# {{{{.ServiceName}}}}.service
+const headerTemplate = `# {{{{.ServiceName}}}}{{{{- if (eq .IdentifySpecifier true) }}}}@{{{{- end}}}}.service
 {{{{- if (eq .GenerateNoHeader false) }}}}
 # autogenerated by Podman {{{{.PodmanVersion}}}}
 {{{{- if .TimeStamp}}}}
@@ -32,7 +32,7 @@ const headerTemplate = `# {{{{.ServiceName}}}}.service
 {{{{- end}}}}
 
 [Unit]
-Description=Podman {{{{.ServiceName}}}}.service
+Description=Podman {{{{.ServiceName}}}}.service{{{{- if (eq .IdentifySpecifier true) }}}} for %I{{{{- end}}}}
 Documentation=man:podman-generate-systemd(1)
 Wants=network-online.target
 After=network-online.target
diff --git a/pkg/systemd/generate/containers.go b/pkg/systemd/generate/containers.go
index 037652a6d..c0a49c614 100644
--- a/pkg/systemd/generate/containers.go
+++ b/pkg/systemd/generate/containers.go
@@ -90,6 +90,8 @@ type containerInfo struct {
 	// Location of the RunRoot for the container.  Required for ensuring the tmpfs
 	// or volume exists and is mounted when coming online at boot.
 	RunRoot string
+	// Add %i and %I to description and execute parts
+	IdentifySpecifier bool
 }
 
 const containerTemplate = headerTemplate + `
@@ -99,7 +101,7 @@ After={{{{- range $index, $value := .BoundToServices -}}}}{{{{if $index}}}} {{{{
 {{{{- end}}}}
 
 [Service]
-Environment={{{{.EnvVariable}}}}=%n
+Environment={{{{.EnvVariable}}}}=%n{{{{- if (eq .IdentifySpecifier true) }}}}-%i{{{{- end}}}}
 {{{{- if .ExtraEnvs}}}}
 Environment={{{{- range $index, $value := .ExtraEnvs -}}}}{{{{if $index}}}} {{{{end}}}}{{{{ $value }}}}{{{{end}}}}
 {{{{- end}}}}
@@ -273,7 +275,6 @@ func executeContainerTemplate(info *containerInfo, options entities.GenerateSyst
 			"--rm",
 		)
 		remainingCmd := info.CreateCommand[index:]
-
 		// Presence check for certain flags/options.
 		fs := pflag.NewFlagSet("args", pflag.ContinueOnError)
 		fs.ParseErrorsWhitelist.UnknownFlags = true
@@ -389,6 +390,32 @@ func executeContainerTemplate(info *containerInfo, options entities.GenerateSyst
 
 		startCommand = append(startCommand, remainingCmd...)
 		startCommand = escapeSystemdArguments(startCommand)
+		if options.TemplateUnitFile {
+			info.IdentifySpecifier = true
+			runIx := -1
+			nameIx := -1
+			for argIx, arg := range startCommand {
+				if arg == "run" {
+					runIx = argIx
+					continue
+				}
+				if arg == "--name" {
+					nameIx = argIx + 1
+					break
+				}
+				if strings.HasPrefix(arg, "--name=") {
+					nameIx = argIx
+					break
+				}
+			}
+			if nameIx == -1 {
+				startCommand = append(startCommand[:runIx+1], startCommand[runIx:]...)
+				startCommand[runIx+1] = fmt.Sprintf("--name=%s-%%i", info.ServiceName)
+				fmt.Println(startCommand)
+			} else {
+				startCommand[nameIx] = fmt.Sprintf("%s-%%i", startCommand[nameIx])
+			}
+		}
 		info.ExecStart = strings.Join(startCommand, " ")
 	}
 
diff --git a/pkg/systemd/generate/pods.go b/pkg/systemd/generate/pods.go
index e755b8eea..38f7e8e3e 100644
--- a/pkg/systemd/generate/pods.go
+++ b/pkg/systemd/generate/pods.go
@@ -79,6 +79,8 @@ type podInfo struct {
 	// Location of the RunRoot for the pod.  Required for ensuring the tmpfs
 	// or volume exists and is mounted when coming online at boot.
 	RunRoot string
+	// Add %i and %I to description and execute parts - this should not be used
+	IdentifySpecifier bool
 }
 
 const podTemplate = headerTemplate + `Requires={{{{- range $index, $value := .RequiredServices -}}}}{{{{if $index}}}} {{{{end}}}}{{{{ $value }}}}.service{{{{end}}}}
@@ -108,6 +110,9 @@ WantedBy=multi-user.target default.target
 // Based on the options, the return value might be the content of all units or
 // the files they been written to.
 func PodUnits(pod *libpod.Pod, options entities.GenerateSystemdOptions) (map[string]string, error) {
+	if options.TemplateUnitFile {
+		return nil, errors.New("--template is not supported for pods")
+	}
 	// Error out if the pod has no infra container, which we require to be the
 	// main service.
 	if !pod.HasInfraContainer() {